Systems and methods for breakaway RFID tags

RELATED APPLICATIONS INFORMATION

This present application claims the benefit of priority as a Continuation under 35 U.S.C. §120 of U.S. patent application Ser. No. 11/766,737, filed Jun. 21, 2007, entitled “Systems and Methods for Breakaway RFID Tags,” which in turn claims the benefit of priority under 35 U.S.C. 119(e) to Provisional Patent Application Ser. No. 60/805,423, entitled “An RFID Smart Cabinet and a Multi-Document Read Write Station,” filed Jun. 21, 2006, all of which are incorporated herein by reference as if set forth in full.

BACKGROUND

1. Field of the Invention

The field of the invention relates generally to Radio Frequency Identification (RFID) systems and more particularly to the design and construction of RFID tags used for tracking the assembly of various devices.

2. Background of the Invention

In complex manufacturing processes, such as the manufacturing of consumer electronics, hundreds or even thousands of parts are assembled to make a single device. It is important to track these components as they go through the manufacturing process. Often logs are used to track components using some form of serial number as they go through the manufacturing process; however, as smaller components get assembled into larger components and ultimately into the end device it can be difficult to continue tracking such components. Moreover, current logging systems can be disparate and difficult to correlate information associated with a specific component.

In certain situations, bar codes or other technology can be used to assist in tracking components as they are assembled in the manufacturing process. Thus, as a component comes to a new station from the manufacturing process it can be scanned, e.g., using a bar code scanner, and information related to the component can be tracked in an electronic database. RFID technology has the added advantage in that line of sight is not required to effectively scan an RFID tag being used to track a component. Even with RFID technology, however, it can be difficult to continue tracking components as they are assembled in the larger assembles because even though line of sight is not required, other components and circuitry can interfere with the ability to effectively read an REID tag once a component associated with the tag has been assembled into a larger device.

The inability to efficiently track components up to the device level hinders the ability to efficiently track information that can used to spot trends, such as the failure trends, to assist in servicing failed devices, and in keeping efficient inventory records.

SUMMARY

A breakaway RFID tag is configured such that it comprises part of a Printed Circuit Board Assembly (PCB). Thus, the breakaway RFID tag can be used to track the PCB as it migrates through a manufacturing process. In one embodiment, the RFID tag can be assembled first and then used to track the PCB as it is populated with components and installed into larger assemblies and ultimately into the end device. Once the PCB is installed into a larger assembly or the end device, the breakaway RFID tag is configured such that it can be broken off and attached to the outside of the larger assembly or end device. In this manner, the RFID tag can be used to continue tracking the PCB all the way through the end of the manufacturing process. Accordingly, tracking information can be more efficiently correlated and used to improve inventory tracking, failure trend spotting analysis, and to improve service by providing information that can quickly identify potential problems in a failed field unit.

These and other features, aspects, and embodiments of the invention are described below in the section entitled “Detailed Description.”

BRIEF DESCRIPTION OF THE DRAWINGS

Features, aspects, and embodiments of the inventions are described in conjunction with the accompanying drawings, in which:

<figref idref="DRAWINGS">FIG. 1</figref> is a diagram illustrating an exemplary RFID system;

<figref idref="DRAWINGS">FIG. 2</figref> is a diagram illustrating an example printed circuit board comprising a breakaway RFID tag in accordance with one embodiment of the inventor;

<figref idref="DRAWINGS">FIG. 3</figref> is a diagram illustrating an example method for tracking an assembly process using the breakaway RFID tag of <figref idref="DRAWINGS">FIG. 2</figref> in accordance with one embodiment of the invention;

<figref idref="DRAWINGS">FIG. 4</figref> is a diagram illustrating an example of assembly process for the printed circuit board of <figref idref="DRAWINGS">FIG. 2</figref>; and,

<figref idref="DRAWINGS">FIG. 5</figref> is a diagram illustrating a method of troubleshooting an assembly process using information retrieved from the breakaway RFID tag of <figref idref="DRAWINGS">FIG. 2</figref>.

DETAILED DESCRIPTION

<figref idref="DRAWINGS">FIG. 1</figref> is a diagram illustrating an exemplary RFID system <b>100</b>. As can be seen RFID system <b>100</b> comprises an RFID interrogator <b>102</b>, an antenna or a coil <b>108</b>, and a transponder, or RFID tag <b>112</b>. RFID interrogator <b>102</b> communicates with RFID tag <b>112</b> over an RF communication channel <b>136</b>. RFID tag <b>112</b> can be passive or active. In the active case, RFID tag <b>112</b> can comprise its own power source, which can allow it to store more information. In the passive case, RFID tag <b>112</b> uses the energy in the signal received over RF channel <b>136</b> to power up a small transponder circuit. The transponder circuit is configured to read the instructions transmitted by RFID interrogator over RF channel <b>136</b> and respond accordingly. Often, the instructions received from RFID interrogator <b>102</b> require the transponder circuit to read a small amount of information stored in a memory circuit on RFID tag <b>112</b> and transmit the information back to RFID interrogator <b>102</b> over RF channel <b>136</b>. The passive RFID tag <b>112</b> typically does not generate an RF signal to be transmitted over RF channel <b>136</b>. Rather, RFID tag <b>112</b> simply reflects the received RF signal, while encoding the data retrieved from memory onto the reflected signal.

Thus, a passive RFID tag comprises a coil, or some form of antenna, and a transponder circuit. A transponder circuit can also include memory circuits for use as described above. The coil or antenna can comprise traces deposited onto a substrate in the same way that traces are deposited onto a PCB substrate. Accordingly, an RFID tag can be manufactured using a PCB substrate with printed traces forming the antenna or coil as well as pads configured to receive a transponder IC. In the systems and methods described below, the ability to make an RFID tag using a PCB substrate and traces is taken advantage of to track the PCB state assembly process by manufacturing the PCBs with a breakaway RFID tag that can be used to track the PCB as components are populated thereon and as the PCB is assembled into larger component assemblies and/or into the end device.

<figref idref="DRAWINGS">FIG. 2</figref> is a diagram illustrating an example Printed Circuit Board (PCB) <b>200</b> comprising a breakaway RFID tag <b>201</b> connected to main body <b>205</b> by a breakaway connection <b>204</b> in accordance with one embodiment of the invention. Main body <b>205</b> can comprise traces for interconnecting other components that are essential to the functioning of the assembled PCB <b>200</b>. Breakaway RFID tag <b>200</b> can comprise a printed antenna <b>202</b> and an integrated circuit (IC) pad <b>203</b>. IC pad <b>203</b> can be configured to receive an RFID transponder IC <b>206</b>. Thus, IC pad <b>203</b> can be of several types, depending on the processes and technology used for a particular implementation. For example, IC pad <b>206</b> can comprise a surface mount pad or a dual axial lead pad, just to name a couple.

Accordingly, breakaway RFID tag <b>201</b> can be populated, e.g., with transponder IC <b>206</b>, before main body <b>205</b> is populated with any associated components. A breakaway RFID tag can then be used to begin tracking information related to the assembly of main body portion <b>205</b> until main body portion <b>205</b> is to be assembled into a larger component assembly. The breakaway RFID tag can then be broken away from main body portion <b>205</b> by breaking breakaway connection <b>204</b>. The breakaway connection <b>204</b> can then used to continue tracking the component assembly into which main body portion <b>205</b> was assembled. Thus, breakaway connection <b>204</b> can simply comprise a narrow portion of PCB substrate that can be snapped off when required. Alternatively, breakaway connection <b>204</b> can comprise a PCB substrate that is perforated with holes in order to make it easier to snap off and break away RFID tag <b>101</b>. In other embodiments, breakaway connection <b>204</b> can be configured such that it can be cut, i.e., using a knife, scissors, or the like, or even sawed in order to disconnect breakaway RFID tag <b>201</b> from main body portion <b>205</b>.

<figref idref="DRAWINGS">FIG. 3</figref> is a flowchart illustrating an example method for tracking an assembly process using, e.g., breakaway RFID tag <b>201</b> in accordance with one embodiment of the systems and methods described herein. First, in step <b>301</b>, a PCB <b>200</b> comprising main body portion <b>205</b>, breakaway connection <b>204</b>, and breakaway RFID tag <b>201</b> is fabricated using known fabrication techniques. Again, breakaway RFID tag <b>201</b> should at least include a printed coil, or antenna, <b>202</b> and an IC pad <b>203</b>. IC pad <b>203</b> can be of several types, e.g., including a surface mount pad or a dual axial lead pad. Main body portion <b>205</b> can contain pads and interconnects for assembling and connecting other components.

After fabricating PCB <b>200</b> with breakaway tag <b>201</b>, IC pad <b>203</b> can be populated with an RFID transponder IC <b>206</b> in step <b>302</b>. RFID transponder IC <b>206</b> can be populated onto breakaway RFID tag <b>201</b> using a number of different methods, including surface mounting or dual axial lead mounting, depending on the type of transponder IC <b>206</b> and IC pad <b>203</b>. Once RFID transponder <b>206</b> has been assembled onto breakaway RFID tag <b>201</b>, RFID tag <b>201</b> can be scanned to record any associated identification information in step <b>303</b>. The recorded identification information can, for example, be used for tracking or troubleshooting as will be described below. In addition to the identification information, other information such as the time, can be recorded as well.

In certain embodiments, PCB <b>200</b> can then be assembled into a larger assembly without any further processing, as illustrated in step <b>208</b>. Once PCB <b>200</b> is assembled into a larger assembly, breakaway RFID tag <b>201</b> can be detached from main body portion <b>205</b> and attached to the exterior surface of the assembly, as illustrated in step <b>309</b>. As mentioned above, placing breakaway RFID tag <b>201</b> on the exterior surface of the assembly allows breakaway RFID tag <b>201</b> to continue performing its tracking function once main body portion <b>205</b> has been incorporated within the assembly. Thus, breakaway RFID tag <b>201</b> can be used to track the assembly into which main body portion <b>205</b> has been assembled. Tracking can be performed simply by scanning, in step <b>310</b>, breakaway RFID tag <b>201</b> and recording its identifying information. In addition to the identifying information for each breakaway RFID tag <b>201</b>, it is possible to record other information such as the time of the scan.

PCB <b>200</b> can, however, be subject to further assembly processes before it is incorporated into a larger assembly in step <b>308</b>. For example, main body portion <b>205</b> can be populated with other components in multiple processing steps, as illustrated in step <b>304</b>. After each additional processing step <b>304</b>, breakaway RFID to <b>201</b>, which can still be attached to main body portion <b>205</b>, can be scanned and recorded in step <b>305</b>. The additional processing performed on the PCB <b>204</b> may consist of many smaller steps. Thus, several additional processing steps <b>304</b> are required, breakaway RFID tag <b>301</b> can be scanned and information recorded after each step.

Breakaway RFID to <b>201</b> can also be used to track and/or record when repairs, or abnormal processing steps, occur in relation to main body portion <b>205</b>. Thus, if it is determined, in step <b>306</b>, that repairs are needed, then PCB <b>200</b> can be routed to a repair station. Breakaway RFID tag can be used to track the occurrence of the repair, e.g., scanning, in step <b>307</b>, breakaway RFID tag <b>201</b> as PCB <b>200</b> enters and/or exits the repair station to record the identifying information of breakaway RFID tag <b>201</b> and, optionally, additional information.

As should be apparent, scanning RFID tag <b>201</b> at various steps in the assembly process can enable the creation of a database of information related to the assembly process for a particular PCB <b>200</b>. RFID tag <b>201</b> will often be a passive RFID tag and therefore comprise a limited amount of information. Accordingly, RFID tag <b>201</b> will often be used to store little more than an identifier associated with PCB <b>200</b>; however, by integrating the RFID scanners used to scan information from RFID tags <b>201</b> with a larger tracking system, assembly operators can provide detailed information for each PCB <b>200</b> and associated with the identifier scanned from the associated RFID tag <b>201</b>. For example, if a PCB <b>200</b> enters a repair station, then the associated breakaway RFID tag <b>201</b> can be scanned and then information related to the repairs can be entered, e.g., through a computer. A scanned identifier and related information can then be stored into a database for later retrieval and use. One such use, would be in servicing a failed unit that has been fielded, i.e., sold to a consumer or end user. This is described in more detail below.

Similarly, breakaway RFID tag <b>201</b> can be used to track and/or record repairs to the assembly after breakaway RFID tag <b>201</b> has been attached to the exterior of the assembly in step <b>309</b>, as illustrated by step <b>310</b>. Thus, if it is determined in step <b>311</b> that repairs are needed, then they can be made and then those repairs traced using breakaway RFID tags <b>201</b>. This can be done by scanning breakaway RFID tag <b>201</b> as the assembly enters and/or exits the repair station to record the identifying information of breakaway RFID tag <b>201</b> and, optionally, additional information in step <b>312</b>.

<figref idref="DRAWINGS">FIG. 4</figref> to the diagram is illustrating an example assembly process for a PCB <b>200</b> comprising a breakaway RFID tag <b>201</b> in accordance with one embodiment of the systems and methods described herein. Thus, as can be seen, the assembly process comprises three assembly steps, step 1, step 2, and step 3, performed at the PCB level. As PCB <b>200</b> enters assembly step 1, RFID tag <b>201</b> can be scanned by an RFID scanner <b>404</b>. Similarly, as PCB <b>200</b> enters step 2 and step 3, RFID tag <b>201</b> can again be scanned by an RFID scanner <b>404</b>. Depending on the embodiment, RFID tag <b>201</b> can also be scanned by an RFID scanner <b>404</b> as it exits one or more of assembly steps 1, 2 and 3.

In addition, RFID scanners <b>404</b> can be interfaced with computer stations <b>402</b>. Computer stations <b>402</b> can be used to input information related to the assembly of PCB <b>200</b>. Any such information, can be associated with information scanned from the associated RFID tag <b>201</b>. Computer stations <b>402</b> can then be interfaced with a central server <b>408</b> so that the scanned information, and any information input through a computer terminal <b>402</b> can be stored in a database <b>410</b> interfaced with or included in central server <b>408</b>.

Depending on the embodiment, or on the step in the assembly process, little more than the identifying information, and possibly a time step, can be noted in order to attract the assembly of PCB <b>200</b>; however, if there is a problem in the assembly of PCB <b>200</b>, then it is often necessary to record additional information so that details related to the problem can be stored in database <b>410</b>. For example, as illustrated in <figref idref="DRAWINGS">FIG. 4</figref>, PCB <b>200</b> may need to enter a repair station during the assembly process. Thus, RFID tag <b>201</b> can be scanned as it enters the repair station and information related to the nature of the repairs can be entered through computer terminal <b>402</b> and stored in database <b>410</b>.

Once PCB <b>200</b> has passed through assembly steps 1, 2, and 3, and possibly the repair station, it can be assembled into a larger component assembly in the final assembly step for PCB <b>200</b>. At this point, breakaway RFID tag <b>201</b> can be broken off, or otherwise detached from PCB <b>200</b>, and attached to the outside of the final assembly <b>406</b>. RFID tag <b>201</b> can then be used to track final assembly <b>406</b>. Such tracking can include, for example, tracking information related to any repairs made on final assembly <b>406</b> as described above.

It should be noted, that in certain embodiments of RFID scanner <b>404</b>, RFID scanner <b>404</b> can include a computer system. Thus, computer terminal <b>402</b> may not be needed in order to interface RFID scanner <b>404</b> with central server <b>408</b>. Alternatively, even if RFID scanner <b>404</b> includes a computer system, then it can still be interfaced with a computer terminal <b>402</b> if required by a particular implementation.

Once RFID tag <b>201</b> is attached to the outside of assembly <b>406</b>, it can remain there and be used even after assembly <b>406</b> has been fielded, e.g., sold to a consumer. <figref idref="DRAWINGS">FIG. 5</figref> is a flowchart illustrating an example method for using RFID tag <b>201</b> in order to troubleshoot failures in fielded units in accordance with one embodiment of the systems and methods described herein. Thus, for example, if a unit in the field fails, a technician can be dispatched in order to service the unit. The technician can begin servicing the unit by scanning breakaway RFID tag <b>201</b>, in step <b>502</b>, attached to the outside of the unit. In step <b>504</b>, the information scanned can then be used to access information related to the assembly of the unit. In other words, information stored in database <b>410</b> can be accessed and used to identify potential problems with the fielded unit. Thus, in step <b>506</b>, information obtained using the scanned information from RFID tag <b>201</b> can be used to troubleshoot potential problems with the fielded unit. In particular, if PCB <b>200</b> went through a repair station, information related to the repairs can be accessed and analyzed to determine if it is likely that the repairs were insufficient.

Moreover, as the technician troubleshoots and services the fielded unit, information related to the servicing can be associated with the information scanned from RFID tag <b>201</b> and then stored, e.g., in database <b>410</b>. Thus, in step <b>508</b>, information can be tracked and stored over the lifetime of assembly <b>406</b>. The information tracked and stored can, however, easily be correlated and stored for efficient retrieval and use over the lifetime of assembly <b>406</b>.

The information related to servicing of fielded units can be used, for example, to track failure trends and identify problems in the assembly process. For example, if servicing of a plurality of fielded units reveals that the problem is consistently related to portions of PCB <b>200</b> that went through a repair station, then this information could be used to ascertain that the repair processes associated with the repair station are inadequate, or are not being implemented correctly. Similarly, information related to consistent failures in the field can be used to identify problems in the assembly process that are not being detected. This information can then be used to implement processes to identify such problems and to implement repair stations to correct the problems when they are identified.

While certain embodiments of the inventions have been described above, it will be understood that the embodiments described are by way of example only. Accordingly, the inventions should not be limited based on the described embodiments. Rather, the scope of the inventions described herein should only be limited in light of the claims that follow when taken in conjunction with the above description and accompanying drawings.